Abstract: A rotary-cam ball-point pen having an outer sleeve, a rotary-cam mechanism comprised of a cam body provided on the inside of the outer sleeve, a rotary-cam engaging the cam body, and a cam bar engaging the rotary-cam, and a refill. The rear portion of the refill is loaded backward by an elastic body inserted into the rotary-cam. The cam bar has a structure with flexibility in which the cam bar can be distorted inward by applying a radial force. Since the cam bar is inserted into the outer sleeve from the rear side of the outer sleeve, it is possible to form a clip of an integral part of the cam bar, or a decoration having dimensions larger than the outside diameter, or a knocking cap.